Different designs, explosion-proof and watertight versions are available. Easy assembly. Applicable for rooms up to 80m². Parasitic noise and resonance are perfectly eliminated by the digital filters of these microphones. Whether conference rooms, corridors, prison cells, bus or train: wherever there is verbal communication our  PKI 2525 Special Room Monitoring Microphone listen in. On request, we can also deliver camouflaged versions (smoke detector, pinhole, outdoor design, etc.).